The RKZ is a zone on an airport takeoff runway between two points called V1 and VR that every large multi-engine jet aircraft, such as Air Force One, must pass through while taking off.

Here is a cockpit video of a 747-400 where the co-pilot can be heard to call out V1″ at 1:24 and then call out rotate (VR) at 1:30, as required for all takeoffs. The runway zone travelled by the aircraft in the 6 seconds between V1 and VR for this takeoff is the RKZ.

If any two engines on a large multi-engine jet can be disabled in the RKZ by a terrorist attack, the aircraft will not be able to gain enough altitude to return to the airport and will almost certainly crash. The availability of inexpensive, GPS-guided autonomous model aircraft and helicopters (drones and UAVs) that are capable of precisely targeting the runway path of each jet engine in the RKZ makes terrorist attacks increasingly probable.

How big a target for terrorists is the intake turbofan of a Boeing 747 jet engine coming down the runway in the RKZ?

The intake fan diameter of the GE CF6-80C2 turbofan used on Air Force One or a 747-400 is 93 inches (2.36 m) or nearly 8 feet wide (7 ft 9 in).

This is a serious charge, and one that I considered long and hard before going public with the exposure of the V1-VR Runway Kill Zone.

I kept it to myself for nearly six years after stumbling onto the concept in 2006, sharing it with the chief research officer of the Air Force and being told that I was the first one to bring it to their attention and did not object to me going public with it.

I asked myself how I would feel if terrorists destroyed a fully loaded passenger plane because the Runway Kill Zone vulnerability had not been defended against and the public had not been educated to be vigilant regarding drone activities near airports or near the POTUS.

After 9-11, how did the people who warned that unlocked cockpit doors would enable terrorists to turn airliners into flying suicide bombs capable of decapitating the US government? Would they have been called tinfoil, nutcase chicken-littles needlessly alarming themselves and the flying public? Absolutely. Now we should know better, OMO.

On 9-11, the passengers of only one of four jets counter-attacked the terrorists. They were educated by hearing over cellphones what could be in store for them and the nation. Better that they had been educated before 9-11 because passengers of ALL FOUR of the jets might have rebelled or better yet, locks would have been placed on cockpit doors.

I have concluded that it is patriotic to sound the alarm when a national security vulnerability is identified and to do whatever I can to educate the public and officials on how to identify a potential threat and to advocate for reasonable defensive measures.

Terrorists are not stupid, they are way ahead of the US government and the public in their use of creative opportunistic inexpensive asymmetric attacks...exactly like the opportunity presented every time a jetliner takes off.

If a fair-minded person spends a lot of time, as I have, on US government and defense-oriented public websites, every day new attack vectors that terrorists could exploit are discussed and war-gamed as to defenses. I believe it is obvious that discussion of the Runway Kill Zone is totally appropriate and does not violate Loose lips sinks ships.

Check out the former NTSB aviation security expert on the CBS NY affiliate immediately declaring the JFK drone event could be a terrorist attack and speculating that a drone could be directed into a jet engine achieving the same result as happened with Captain Sully (with video of the crash provided to the public) exactly as described on the Runway Kill Zone blog:

“That assumes that the drone knows the exact altitude at which the aircraft will cross over a given point on the ground, and that it will not drift sideways from the runway centerline after takeoff.”

If you read down into the blog this issue is extensively discussed.

On each airframe, such as a 747-400, each engine is mounted at a known distance to the left or right of the centerline and at a predictable altitude from the runway surface during takeoff (allowing for wing lift of the outer engines).

If you go onto Google Earth, for example, you can find any airport and hover your pointer at each end of any runway centerline to obtain the GPS coordinates for latitude, longitude and altitude. Knowing the three-dimensional coordinates for each end of the runway centerline and the known distance that each engine is from the airframe centerline, say of a 747-400, allows the individual linear path down the runway that each engine will follow.

This allows each engine of that specific airframe to be targeted by terrorists.

“If I recall correctly, the certification requirements for four-engine civil aircraft are that they be able to maintain a ‘positive climb rate’ if they lose two engines on takeoff.”

It is only the loss of ONE engine, the “critical engine” (term of art) for which a positive rate of climb is required for each take-off. Pilots must calculate this as part of flight prep to determine V1.

“I think the article is concerned about the time between when the aircraft is going too fast to stop on the runway, but still too slow to take off.”

Correct.

If you read down into the blog post, this is discussed extensively with numerous informative links and Youtubes provided.

From the blog link:

What is V1?

According to Wikipedia V1 is the critical engine failure recognition speed or takeoff decision speed. It is the decision speed nominated by the pilot which satisfies all safety rules, and above which the takeoff will continue even if an engine fails. The speed will vary between aircraft types and also due to aircraft weight, runway length, wing flap setting, engine thrust used, runway surface contamination and other factors.

What is VR?

Per Wikipedia VR is rotation speed, the speed at which the aircrafts nose wheel leaves the ground. When the aircraft reaches VR, the pilot pulls back on the yoke causing the nose of the aircraft to rotate upwards and causing the wing and flap takeoff configuration to generate lift sufficient to raise the aircraft off the runway.

Why does the RKZ begin way down the runway at V1 and not back at the beginning of the runway?

In the event of a terrorist attack on the engines of an aircraft during take-off, if the attack were to occur while accelerating at any speed below V1, the pilots should be able to abandon the takeoff safely by rejecting the takeoff.

“This allows each engine of that specific airframe to be targeted by terrorists.”

Not really Load weight determines the speed of acceleration and a terrorist would need to know the weight and takeoff performance of the aircraft to know when the aircraft will be at a specific point and the terrorist would need to know the acceleration and performance characteristics of their weapon to get the weapon and the engine to be at the same place at the same time. Sorry, but implausible.

12
posted on 05/04/2013 10:17:29 AM PDT
by CodeToad
(Liberals are bloodsucking ticks. We need to light the matchstick to burn them off.)

A radio transmitter, placed in the vicinity of the normal VR location, using low power, transmitting conflicting control signals could possibly defeat any attempts by someone hoping to use a drone to effect the crash of a heavy commercial aircraft. I am not sure how this would affect the Airbus - fly by wire aircraft.

“:A radio transmitter, placed in the vicinity of the normal VR location, using low power, transmitting conflicting control signals could possibly defeat any attempts by someone hoping to use a drone to effect the crash of a heavy commercial aircraft. I am not sure how this would affect the Airbus - fly by wire aircraft”

Just how, exactly, does a fly-by-wire aircraft be interfered with by RF signals?

17
posted on 05/04/2013 10:33:14 AM PDT
by CodeToad
(Liberals are bloodsucking ticks. We need to light the matchstick to burn them off.)

30K wind directly down the runway is a huge difference from a dead calm.

And dead calm at 100F vs 30K at 15F.....

Geese hit the engines by sheer luck. A cloud of small drones blanketing the departure path might get a large jet but one drone in the constantly varying flight path is not going to happen.

The drone operator would have to know the numbers for each model aircraft, TO weight, effect of wind, temp, field elevation, pressure...and then would have to be able to control the drone so as to have it in the exact spot required....

It would be easier to put 200 drones in the departure corridor and destroy more than one engine.

“A radio transmitter, placed in the vicinity of the normal VR location, using low power, transmitting conflicting control signals could possibly defeat any attempts by someone hoping to use a drone to effect the crash of a heavy commercial aircraft.”

If you read down the blog at the link the inexpensive GPS/inertial autopilots that are available for model aircraft are discussed and links provided.

Model aircraft equipped with GPS/inertial autopilots DO NOT rely exclusively on radio control. If the location of an engine at VR at the end of the Runway Kill Zone can be calculated in three dimensions with near certainty for a specific airframe, such as a 747-400, the runway can be “mined” by programing the drone copter to proceed to that location as a “waypoint.” No further RC commands would be needed.

“Not really Load weight determines the speed of acceleration and a terrorist would need to know the weight and takeoff performance of the aircraft to know when the aircraft will be at a specific point and the terrorist would need to know the acceleration and performance characteristics of their weapon to get the weapon and the engine to be at the same place at the same time.”

I disagree strongly. BTW, three out of four of the 9-11 attacks using three separate “implausible” strategies were successful.

I guarantees that if you go to an airport where the same fully loaded 747 (passengers, cargo and fuel) takes off every day on a regularly scheduled flight, the V1-VR zone for the take-off.

This blog post was written a year ago and the new capabilities of minicopters hadn’t been fully apparent to me so, yes I was contemplating terrorist use of model jet turbine aircraft to make an attack which requires calculating trying to get the drone to the RKZ and the same time the airliner arrives there, but...

...mini-copter can be instructed to proceed to a three-dimensional waypoint in the runway path of an engine and just sit there waiting for the engine to come speeding down the runway to collide with it. It would have no radar return and could be hidden in grass nearby and instructed to pop-up and go to the waypoint at the last minute, for example.

Nope. If you knew anything about large aircraft you wouldnt have said such a thing. That point changes significantly.

I didn’t say “the same type” aircraft. I said, “the same scheduled airliner”. Passenger loads vary day to day but your Monday AM or Friday last PM birds are normally jam packed to capacity.

Cargo planes are the same during gift associated holidays. All Fed Ex birds are flying at weight capacity during the Christmas rush. Their VR points are all going to be very similar for type and model aircraft. Data which is easily determined by the N numbers.

That I have no idea of. Did you notice that I said “I am not sure how this would affect the Airbus - fly by wire aircraft If your Smart phone must be turned off for takeoff and landing they are susceptible to radio waves, I presume. I don’t know anything about Airbus aircraft except I have waited in line behind them to takeoff.

“The drone operator would have to know the numbers for each model aircraft, TO weight, effect of wind, temp, field elevation, pressure...and then would have to be able to control the drone so as to have it in the exact spot required....”

True, and entirely within the capacity of, for example, the planners of 9-11.

I would expect a terrorist to focus on one and only one high value airframe for a particular attack plan (a particular 747-200B comes to mind, to start with, but that would be a “hard target”). Multiple attack variables could be programed into the control station of the drone and at the last minute the variables for a particular airframe could be sent to the drone.

If a person reads down the whole blog and goes to the supporting links and videos, I think this kind of attack will be seen as more feasible.

The FBI and an NTSB investigator certainly thought making such an attack in the air in three dimensions miles from the airport in a Landing Approach Kill Zone (LAKZ...blog pending) as can be seen at the bottom of my opening comment to JR.

“It wont be quite so easy as there has to be a dozen different models of the 400. I think the latest is 747-400XQLR. Each aircraft has a different base weight and capacity weight that comes into play.”

But, IIRC, all 747-400s have the engines mounted exactly at the same distance from the centerline, for starters. Daily observation, as was previously pointed out, could nail down VR for a particular scheduled flight.

BTW, on the blog there are links to a 747 takeoff cockpit Youtube there is a great head-on Youtube of a 747 during takeoff shot straight down the runway from a public access location. A terrorist with only an RC airframe might even achieve a direct hit from such a vantage point where only TWO dimensions are involved!

Yep. The only way I see a drone operator hitting an engine of a 747 is with visual guidance and with some luck still. Doable but there are far more effective and less risky means to harm airplanes in Afghanistan.

29
posted on 05/04/2013 3:04:23 PM PDT
by CodeToad
(Liberals are bloodsucking ticks. We need to light the matchstick to burn them off.)

“If your Smart phone must be turned off for takeoff and landing they are susceptible to radio waves, I presume.”

Unfortunately, that presumption has been around even in the aviation community. However, I can guarantee you there has not been a single incident of a smartphone interfering with flight control systems or even navigation systems. In fact, the FAR, Federal Aviation Regulations, in no way require devices to be turned off. The FAR simply gives the PIC, Pilot in Command, the authority over that decision. The FCC disallows phones in the air to protect cell towers from being bombarded by signals at altitude where phones may hit dozens or even hundreds of towers at once. Cell system operators asked for that regulation.

31
posted on 05/04/2013 3:09:35 PM PDT
by CodeToad
(Liberals are bloodsucking ticks. We need to light the matchstick to burn them off.)

If we are to become paranoid about what someone can do then we must lock down everything and close all roadways. I could easily just bump you at highway speed from the road and maybe kill you. I could knock you over as you road a bicycle. We could even just push you down a flight of stairs.

There are no protections in the real world from all evil. It is a simple fact of life.

32
posted on 05/04/2013 3:11:40 PM PDT
by CodeToad
(Liberals are bloodsucking ticks. We need to light the matchstick to burn them off.)

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